Comment by nerd_stuff | Hacker News Reader

Comment by nerd_stuff | Hacker News Reader

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> Relativity overturned Newtonian mechanics in the same way that Copernican cosmology overturned Ptotomeic cosomology.......So are these revolutions somehow categorically different?

They're so different that I'm surprised it's even a question. If anything the illusion of mind is bending them to fit a narrative.

When Relativity explained the precession of Mercury's perihelion the existing physics was off by 1/12,000,000th of Mercury's orbit (per orbit.) Not only was the Ptolemic system off by entire degrees (as opposed to arcseconds which are 1/3,600th of a degree) it was highly dependent on the position of the observer, if you stood on Jupiter I imagine the Ptolemic system would give you complete nonsense as to where the planets would be.

More importantly Newton's work has never been thrown out and you can derive classical mechanics as a special case of Relativity. You can also derive it from quantum mechanics. I don't believe you can show that the geocentric model of the solar system is a special case of the heliocentric model.

Newtoninan mechanics were once thought to be based on a set of laws. Settled truth, it was thought. A law is no longer a law when it fails to hold under particular conditions, although it might still be useful. The bulk of practical human knowledge fall into this same category. All current laws will eventually find their way there too.

Conditions where relativity manifests seem way out extreme to us today. How extreme would standing on Jupiter have seemed in 1500 when your goal is not to land a rocket on the moon but to develop a more accurate calendar or navigate the Mediterranean? What will they say of Newtonian mechanics after 500 more years of hindsight?

A point that Kuhn makes in his book is that yes, Newtonian mechanics is still very useful, but relativity demonstrated that it is wrong. That is, Newtonian mechanics implies that we live in a particular kind of universe. That implication is false. No matter how useful Newtonian mechanics is, no matter how close it is to being correct in the situation we're familiar with, it is wrong, and the implications of the kind of universe we live in is not correct. That is huge, as it required that the people who think about this for a living (physicists) had to change how they thought completely.

I recommend reading the book, as he goes into this kind of objection. One of his main points about the paradigm shift is that afterwards, the way scientists think about the problems has changed, and as a result, the kind of questions they ask - or even can ask - has changed.

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